Connectable elastomeric drive belts have long been used on live-roller conveyors where it is either impractical or impossible to install continuous belts which interconnect two or more rollers or a roller and a drive shaft. These belts are also referred to in the trade as "Quick-Connect".TM. or "zero downtime" belts. Connectable belts are looped about the rollers and the free ends are interconnected by a connector. In many applications the connectable belts are made of polyurethane and are permanently twisted to include a loop at either end. These loops are then interconnected by a plastic or metal connector having two hooks, usually in the form of an "S" or "C" shape.
These twisted elastomeric belts are normally supplied with a hook mounted on one end of the loop. These belts are difficult to install when a belt breaks and must be replaced. To install, one end of the belt must be held static, usually by grasping the free end, while the hook connector is looped around the two rollers and the belt is stretched to enable the end loop to engage the connector hook. The force required to stretch the urethane belt is significant, thus making it extremely difficult, and often impossible, for one person to accomplish this task. This is especially so because the urethane is slippery and only one hand and arm are available to do the stretching, since the other hand must hold the one end static.
Another problem encountered in replacing one of these belts is the physical environment. Frequently, the rollers are closely spaced, or are positioned close to a supporting frame and guards, making the area beneath the rollers nearly inaccessible. Further complications arise with some of the connecting hooks in use, which require that the free end loop be pinched and forced into a narrow hook entry slot, necessitating significant thumb pressure.
The conventional solution to the installation problems chronicled above is to partially disassemble the conveyor rollers to move them closer together, thus avoiding the need to stretch the belt by hand. After the belt is thusly installed, the roller is moved back to its original positioned and secured. This avoids the manual strain, but involves stopping the conveyor system for a significant time period, and is labor intensive and, hence, expensive. This method still requires manual thumb pressure to force the free end loop into the narrow hook entry slot.
A problem common to line-shaft conveyors is the unintentional, but all-too-frequent instance of installing a belt backwards. This will cause the roller to rotate in the wrong direction, a problem identified only after the belt installation is completed. At this point, disconnection of the belt is very difficult and sometimes nearly impossible, because of the belt tension and entrapment of the loops in the hooks by the narrow entry slots. Thus, correction often entails cutting and destroying the newly installed belt, and installing another one.
There is a need for a new method of replacing and installing elastomeric drive belts that is simpler, less labor intensive and less expensive.